Proficiency testing for measurement of total mass and elements in workplace air filters : round 10

In Round 10 of the proficiency testing programme sixteen laboratories in Finland, Sweden, Denmark and Norway have participated from England, Lithuania, Filter and cassettes were distributed to the laboratories in April 2002. The laboratories were asked to pre-weigh the filters prior to exposure to welding fume, and return the prepared filte cassettes by 10th of May 2002. Realistic workroom air and synthetically produced reference filters were distrib r uted to the participants in June 2002. The deadline for reporting results was 9th o f August 2002. The laboratories were asked to measure a number of occupational important th e enclosed protocol (Ag, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn) and total mass. The inter-laboratory variance for the individual a cceptable agreement among the participants.